Morals do not exist.
First, let's discuss what morals are. "It is wrong to kill" sounds like a good starting point. If we dissect that statement, we have basically two parts and an implied third. Something is right or wrong, and that something is an action. The implied third part is a rule that the action that is wrong should not be performed. "It is wrong to kill" implies "do not kill."
That's fine, but are morals really as simple as a rule? A dictate on action? Considering how highly we regard moral concepts, and how frequently they are spoken of in reverent tongues, the idea that they are nothing more than a rule seems antithetical to common thought. I am saying exactly that, though. Morals are nothing more that rules.
Depending on the semantics of the situation, I something classify morals as a very special kind of rule. Namely, a rule without which the system in which the rule applies would cease to function.
I must differentiate morals from ethics at this point. Many people regard the two words as effectively interchangeable. Morals can be part of an ehtical system, and I can be guided by my ethics as a human. Still, I think that the nebulous nature of the two words renders them useless in many terms, and I think that my distinction is one that is commonly held, even if it's rarely stated expressly. Morals are rules are behavior that apply to all humans simply because they are human, and ethics are rules of behavior accepted by an otherwise free person after accepting a certain post without society.
I am morally bound not to steal from anyone, but a doctor is ethically bound to not have sex with his patients. Since I am not a doctor, I am not ethically bound to do anything regarding patients. Truly, I have no patients. So, it seems that ethics could be considered a special class of morals, whereby they are in fact universal (all doctors cannot have sex with patients), but apply only if you become a doctor.
That brings up another aspect of morals: they are universal. They apply to everyone. Ethics possibly apply to everyone, because everyone could possibly become something to which ethics apply, so ethics are morals, just a specific type. Morals are one step up, they are universal if you are human.
My definition of morals are universal rules that are required. A rule against killing is required for society to function. It doesn't necessarily need a law or a large governing body, only a tacit agreement that those within a group won't off one another. I think that this may actually be part of evolutionary programming. Wolves in packs almost never kill one another, but they don't have advanced moral systems. The rule is required because without that recognized rule, society could not function. I'd always be worried about, and defending myself from, my neighbors.
Let's try stealing? There must be some recognition of stealing being bad since without it, the economy wouldn't function. Or lying? Communication would break down if lying wasn't wrong. Many things fall under my definition of morals, but many things that are frequently called moral wrongs do not. Rape is not a moral wrong in my book. A society can in fact function with lots of rape. It might not function terribly well, but it can. And since my morals and ethics are based on groups (humans, doctors, etc.) I could argue that it is not morally wrong to go outside of your group, kill everyone in an opposing group and take their stuff.
I think that for a moral to be a moral though, as opposed to tribal ethics I suppose, it must apply to all humans. I think that history supports this view over the view of tribal ethics allowing my group to kill a neighboring group for their stuff. History has been an irrevocably drive towards a larger, more global community, where my "neighbor" in Africa can be just as close as my neighbor across the street. I can talk with them and see them every day. I can mail things to them overnight. The world is so small, now. The world has also gotten progressively less violent when it comes to hot nation-on-nation action. Not only are morals actions to rules to live by, but the human animal seems to naturally move towards an acceptance of these values. Perhaps it's those mysterious mirror neurons and the empathy machine in action.
Whatever it is, people don't seem to naturally want to kill one another. Or rob from one another. And I think it's obvious why. A world that is low on violence, crime, and hot nation-on-nation action is a world with ever wider boundaries. The limits of what I can achieve and how easy and fun life is expand with increasing numbers of people accepting these rules.
Unfrotunately for my formulation of morals, it doesn't really make it sound like morals. Morals are right and wrong. As such, many people have many different kinds of morals. My formulation has removed the concept of right and wrong and replaced it with a somewhat self-serving economic perspective. That's not what people generally think of when they say the word "morals."
It is because of that, the morals in this popular sense are so fluid and flexible. That what is right for one person is wrong for another, that leads me to only one conclusion, morals do not exist. They exist in my sense of the word, but not in the sense of right and wrong. For example, my arguments work very well against Islamic extremists, but many Americans seem dead-set on saying that the Muslims are amoral monsters, when it's the Muslims saying the same thing about us. There is no firm ground onto which one can build arguments for either case.
Or take this article on Wired. Here, Hummer owners are actually embracing what they see as moral attacks on their viewpoint. So what do they do? Fully convinced of the righteousness of their own morals, they wrap themselves up in the very attacks directed at them, put a patriotic spin on them, and call themselves red-blooded Americans fighting the anti-American bias of the rest of the world. There is no way to win a moral argument, which means you're arguing about nothing, because if you were, someone could win. It would mean there was some substance underlying the conversation.
For example, I could argue that raising prices will increase sales (ignore the fact that newspapers are actually arguing this). But there is substance under this in the form of economics and econometrics. We can turn to measurements and history to show, unequivocally, that raising prices decreases sales. But that doesn't work in morals. I could argue that it's morally wrong to cheat on your wife. But you could argue that it's fine. Both stances are valid. Perhaps your wife doesn't mind that you sleep with other women. Perhaps you'll point out successful polygamous cultures while I'll point out statistics of marriage failure because of cheating.
There is no way to win a moral argument, which means there's no such thing as morals. They are only things that we like and dislike. Are comfortable with or uncomfortable with. I think that moral pursuits should be about finding that elusive solid ground from which unavoidable conclusions can be reached. An economic perspective seems to work well, where we do what's best for us, but that seems dangerously Randian. I think that a good moral argument is against a behavior that, if allowed, either increases danger or decreases freedom of other people. Strangely, many people's arguments against gay marriage is similar to this formulation, whereby they argue that letting gay marriage through would endanger traditional marriage.
Regardless, I think an immoral action is something that increases danger (as in the possibility of physical harm) or decreases freedom for others. I do not believe it is possible to be immoral against yourself. The finer aspects os ethics are complicated, e.g. doctors cannot have sex with patients for fear of psychological harm. Psychological harm can frequently lead to physical harm, but it's a pretty foggy boundary as to where that happens. A doctor cannot have sex with a patient, but I doubt that psychological harm could come from someone seeing pornography on a billboard.
Now that I think of it, perhaps the differentiation comes in the form of emotional harm and psychological harm. Yes, this must be the case or breaking up with a boyfriend would be morally wrong. Yes, you will hurt his feelings, but you will not damage him psychologically. A doctor, with a position of authority over a patient, could cause long-lasting legitimate psychological harm to a patient. Even though that is possible in the breaking up scenario, it is of low likelihood, and trying to avoid all instances of that possible outcome would have a serious impediment on our daily lives. We would be unable to say anything, do anything, or act in almost any way around anyone for the moral fear of hurting them psychologically.
I would argue that morals exist on a spectrum, where breaking up with a boyfriend is indeed morally wrong, but the degree of immorality is low. The immorality of killing your boyfriend is high, so that's where we have a rule. This is somewhat appealing to me, but it does damage to the idea that morals are easily stated rules of behavior that can be universally applied. But really, can anything be universally applied? It's wrong to kill. Unless you are defending yourself. Or a loved one. Or your friend. Or your pet? Or someones property? Or someone's good name? Where is the moral line drawn?
Ah well. My original formulation stands. A moral is a rule without which society could not function. We can break up with our boyfriends and society continues to function. We can kill in self defense and society continues to function. Our doctors can even sleep with their patients, and society continues to function... doctoring might not do too well, but the rest of us will be fine. As that, morals are absolute and easy to determine. Beyond that, morals are nebulous at best, don't exist at all at worst, and barely seem worth discussing either way. So why bother?